Solid Fuel Engines
•Solid fuel engines (SRB’s in the shuttle program) are as the name suggests, a solid “dry” fuel. Two were used on each shuttle launch. •A scenario where a solid fuel can be an advantage is when you might need to launch with no prior preparation. For example, nuclear missiles ready to launch on command inside a silo. •A downside is that solid fuel can not easily be extinguished or relighted. Only recently has this been accomplished with some varied success. Solid fuel also can not be throttled. However, limited steering is possible.
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Actual Shuttle SRB Test Firing
Orion Launch Abort System
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Each Shuttle SRB would burn for a total of 127 seconds during a launch before separation.